The conventional method to create an energy split between a spin-up electron and a spin-down electron in a non-magnetic material is through the Zeeman effect. In particular, electronic configurations that have the same energy can be split in a spin-dependent manner by the introduction of a sufficiently large magnetic field. However, due to the small value of Bohr magneton which defines the magnetic moment of electrons, the observed Zeeman split is generally very small. For example, a 10-Tesla field may cause an energy split of about 1 meV. To create a split of 1 eV, one would therefore need a field on the order of ten thousand Tesla.
Thus, a non-magnetic material is at most paramagnetic with small magnetic susceptibility. Furthermore, even if were possible to split the spin-up and spin-down electron levels by 1 eV via the Zeeman effect, it is still a challenge to create a 1 eV chemical potential difference between spin-up and spin-down electrons inside a material, since the laws of thermodynamics requires chemical potential to be the same at equilibrium.
Another possible way to generate a chemical potential difference inside a material is by applying an electrical bias, however it is difficult to apply a sufficiently large bias on a metal due to its conductivity. Although it may be possible to apply a large bias on a semiconductor or an insulator, this would tend to induce only a chemical potential difference between spatially separated electrons of the same spin. There is to date no device capable of generating a large chemical potential difference between the spin-up and spin-down electrons at the same location.
This Background section is intended to present ideas and concepts that the inventor feels will be of use in understanding the invention. This Background section is not intended to define or explain the prior art and is not intended to indicate that any technique or structure discussed in this section exists anywhere outside of the inventor's conception. Thus, the foregoing is not meant to capture and explain the prior art, but rather to present general ideas that may be of use to the reader in understanding the remainder of the document.